US10809783B2 - Power source system - Google Patents

Power source system Download PDF

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US10809783B2
US10809783B2 US16/055,453 US201816055453A US10809783B2 US 10809783 B2 US10809783 B2 US 10809783B2 US 201816055453 A US201816055453 A US 201816055453A US 10809783 B2 US10809783 B2 US 10809783B2
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power source
power
electric motor
counter
state
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US20190056771A1 (en
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Fumihiko Sato
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JTEKT Corp
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JTEKT Corp
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/04—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/04—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear
    • B62D5/0457—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear characterised by control features of the drive means as such
    • B62D5/046—Controlling the motor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L50/00—Electric propulsion with power supplied within the vehicle
    • B60L50/40—Electric propulsion with power supplied within the vehicle using propulsion power supplied by capacitors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60R—VEHICLES, VEHICLE FITTINGS, OR VEHICLE PARTS, NOT OTHERWISE PROVIDED FOR
    • B60R16/00—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for
    • B60R16/02—Electric or fluid circuits specially adapted for vehicles and not otherwise provided for; Arrangement of elements of electric or fluid circuits specially adapted for vehicles and not otherwise provided for electric constitutive elements
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/04—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear
    • B62D5/0457—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear characterised by control features of the drive means as such
    • B62D5/046—Controlling the motor
    • B62D5/0463—Controlling the motor calculating assisting torque from the motor based on driver input
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62D—MOTOR VEHICLES; TRAILERS
    • B62D5/00—Power-assisted or power-driven steering
    • B62D5/04—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear
    • B62D5/0457—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear characterised by control features of the drive means as such
    • B62D5/0481—Power-assisted or power-driven steering electrical, e.g. using an electric servo-motor connected to, or forming part of, the steering gear characterised by control features of the drive means as such monitoring the steering system, e.g. failures
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06F—ELECTRIC DIGITAL DATA PROCESSING
    • G06F1/00—Details not covered by groups G06F3/00 - G06F13/00 and G06F21/00
    • G06F1/26—Power supply means, e.g. regulation thereof
    • G06F1/263—Arrangements for using multiple switchable power supplies, e.g. battery and AC
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0029—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0029—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
    • H02J7/00302—Overcharge protection
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0029—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries with safety or protection devices or circuits
    • H02J7/00308—Overvoltage protection
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/0068—Battery or charger load switching, e.g. concurrent charging and load supply
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/14—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle
    • H02J7/1415—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle with a generator driven by a prime mover other than the motor of a vehicle
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/14—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle
    • H02J7/1423—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries for charging batteries from dynamo-electric generators driven at varying speed, e.g. on vehicle with multiple batteries
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J7/00—Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J7/34—Parallel operation in networks using both storage and other dc sources, e.g. providing buffering
    • H02J7/342—The other DC source being a battery actively interacting with the first one, i.e. battery to battery charging
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P23/00—Arrangements or methods for the control of AC motors characterised by a control method other than vector control
    • H02P23/14—Estimation or adaptation of motor parameters, e.g. rotor time constant, flux, speed, current or voltage
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K3/00—Circuits for generating electric pulses; Monostable, bistable or multistable circuits
    • H03K3/01—Details
    • H03K3/017—Adjustment of width or dutycycle of pulses
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
    • G01L5/00—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes
    • G01L5/22—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for measuring the force applied to control members, e.g. control members of vehicles, triggers
    • G01L5/221—Apparatus for, or methods of, measuring force, work, mechanical power, or torque, specially adapted for specific purposes for measuring the force applied to control members, e.g. control members of vehicles, triggers to steering wheels, e.g. for power assisted steering
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02J—CIRCUIT ARRANGEMENTS OR SYSTEMS FOR SUPPLYING OR DISTRIBUTING ELECTRIC POWER; SYSTEMS FOR STORING ELECTRIC ENERGY
    • H02J2207/00—Indexing scheme relating to details of circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
    • H02J2207/20—Charging or discharging characterised by the power electronics converter
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K7/00—Modulating pulses with a continuously-variable modulating signal
    • H03K7/08—Duration or width modulation ; Duty cycle modulation
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/60—Other road transportation technologies with climate change mitigation effect
    • Y02T10/70—Energy storage systems for electromobility, e.g. batteries

Definitions

  • the present invention relates to a power source system for use in a vehicle that includes an electric motor.
  • the switching circuit performs switching between a normal output voltage mode, in which power is supplied to the drive circuit by only the main power source, and a high-output voltage mode, in which power is supplied to the drive circuit utilizing both the main power source and the auxiliary power source through discharge of the auxiliary power source.
  • the switching circuit When a high load is imposed on the electric power steering system, the switching circuit sets a power supply mode to the high-output voltage mode. In this case, the auxiliary power source is in a discharge state. When a low load is imposed on the electric power steering system, on the other hand, the switching circuit sets the power supply mode to the normal output voltage mode, and charges the auxiliary power source.
  • Factors that may hinder normal operation of the electric power steering system include generation of a counter-electromotive force due to reverse input to the electric motor.
  • a counter-electromotive force is generated when the operation state of the electric motor is brought into a regeneration state with the electric motor rotated by an external force due to travel on a rocky road or the vehicle riding onto a curb, for example. If a counter-electromotive force due to reverse input is generated when the power supply mode is the high-output voltage mode, the counter-electromotive force is added to the output voltage of the power source device, and a failure may be caused in the electric power steering system because of an overvoltage.
  • An object of the present invention is to provide a power source system that can suppress an excessive output voltage from a power source device when the operation state of an electric motor is brought into a regeneration state.
  • An aspect of the present invention provides a power source system for use in a vehicle that includes an electric motor, the power source system including: a power source device; and a control device that controls the power source device, in which: the power source device includes a main power source, an auxiliary power source, and a switching circuit configured to switch a power supply mode between a first power supply mode, in which power is supplied to a drive circuit for the electric motor by only the main power source, and a second power supply mode, in which power is supplied to the drive circuit utilizing both the main power source and the auxiliary power source; and the control device includes a switching circuit control unit that controls the switching circuit on the basis of a value that matches power consumption by the drive circuit, a determination unit that determines whether an operation state of the electric motor is a regeneration state or a power-running state, and a limitation unit that limits power to be supplied to the drive circuit when the power supply mode is the second power supply mode and it is determined by the determination unit that the operation state of the electric motor is the regeneration state.
  • the power source device
  • FIG. 1 is a schematic diagram illustrating a schematic configuration of an electric power steering system to which a power source system according to an embodiment of the present invention is applied;
  • FIG. 2 is a circuit diagram illustrating the electrical configuration of the electric power steering system of FIG. 1 ;
  • FIG. 3 is a flowchart illustrating operation of a power source control ECU
  • FIG. 4B is a part of the flowchart illustrating the modification of operation of the power source control ECU.
  • FIG. 1 is a schematic diagram illustrating a schematic configuration of an electric power steering system to which a power source system according to an embodiment of the present invention is applied.
  • An electric power steering (EPS) system 1 includes a steering wheel 2 , a steering operation mechanism 4 , and a steering assist mechanism 5 .
  • the steering wheel 2 is a steering member configured to steer the vehicle.
  • the steering operation mechanism 4 steers steered wheels 3 in conjunction with rotation of the steering wheel 2 .
  • the steering assist mechanism 5 assists a driver in steering.
  • the steering wheel 2 and the steering operation mechanism 4 are mechanically coupled to each other via a steering shaft 6 and an intermediate shaft 7 .
  • the steering shaft 6 includes an input shaft 8 and an output shaft 9 .
  • the input shaft 8 is coupled to the steering wheel 2 .
  • the output shaft 9 is coupled to the intermediate shaft 7 .
  • the input shaft 8 and the output shaft 9 are coupled so as to be rotatable relative to each other via a torsion bar 10 .
  • a torque sensor 11 is disposed in the vicinity of the torsion bar 10 . The torque sensor 11 detects steering torque T applied to the steering wheel 2 on the basis of the amount of relative rotational displacement between the input shaft 8 and the output shaft 9 .
  • the steering torque T which is detected by the torque sensor 11 is detected as a positive value when the vehicle is steered to the right, and as a negative value when the vehicle is steered to the left, and the magnitude of the steering torque T is larger as the absolute value of the positive or negative value is larger.
  • the steering operation mechanism 4 is composed of a rack-and-pinion mechanism that includes a pinion shaft 13 and a rack shaft 14 that serves as a steered shaft.
  • the steered wheels 3 are coupled to end portions of the rack shaft 14 via tie rods 15 and knuckle arms (not illustrated).
  • the pinion shaft 13 is coupled to the intermediate shaft 7 .
  • a pinion 16 is coupled to the distal end of the pinion shaft 13 .
  • the rack shaft 14 extends linearly along the right-left direction of the automobile.
  • a rack 17 meshed with the pinion 16 is formed at an intermediate portion of the rack shaft 14 in the axial direction.
  • the pinion 16 and the rack 17 convert rotation of the pinion shaft 13 into movement of the rack shaft 14 in the axial direction.
  • the steered wheels 3 can be steered by moving the rack shaft 14 in the axial direction.
  • the steering assist mechanism 5 includes an electric motor 18 for steering assist, and a speed reducer 19 configured to transfer output torque from the electric motor 18 to the steering operation mechanism 4 .
  • the speed reducer 19 is composed of a worm gear mechanism that includes a worm gear 20 and a worm wheel 21 meshed with the worm gear 20 .
  • the vehicle is provided with a vehicle speed sensor 24 configured to detect a vehicle speed V.
  • the steering torque T which is detected by the torque sensor 11 , the vehicle speed V which is detected by the vehicle speed sensor 24 , and so forth are input to an EPS electronic control unit (ECU) 12 .
  • the EPS ECU 12 performs so-called assist control by controlling the electric motor 18 on the basis of such inputs.
  • Power is supplied to a motor drive circuit 42 and a power source IC 43 (see FIG. 2 ) in the EPS ECU 12 by one or both of a main power source 31 and a capacitor (auxiliary power source) 54 (see FIG. 2 ) in an auxiliary power source device 32 .
  • the auxiliary power source device 32 is controlled by a power source control ECU 33 .
  • the EPS ECU 12 and the power source control ECU 33 are connected to each other via a communication line.
  • the main power source 31 and the auxiliary power source device 32 constitute a power source device 30 .
  • the power source control ECU 33 is an example of a control device that controls the power source device 30 .
  • FIG. 2 is a circuit diagram illustrating the electrical configuration of the electric power steering system 1 .
  • the EPS ECU 12 includes a motor control circuit 41 , the motor drive circuit (inverter circuit) 42 , and the power source IC 43 .
  • the motor control circuit 41 is composed of a microcomputer.
  • the motor drive circuit 42 is controlled by the motor control circuit 41 , and supplies power to the electric motor 18 .
  • the power source IC 43 generates power for the motor control circuit 41 .
  • the EPS ECU 12 receives an output signal from a current sensor 44 configured to detect a motor current that flows through the electric motor 18 .
  • the motor control circuit 41 controls drive of the motor drive circuit 42 on the basis of the steering torque T, the vehicle speed V, and the motor current.
  • the steering torque T is detected by the torque sensor 11 .
  • the vehicle speed V is detected by the vehicle speed sensor 24 .
  • the motor current is detected by the current sensor 44 .
  • the motor control circuit 41 sets a target current value on the basis of the steering torque T and the vehicle speed V, and controls drive of the motor drive circuit 42 such that the motor current which flows through the electric motor 18 is equal to the target current value.
  • the auxiliary power source device 32 is connected in series with the main power source 31 .
  • the auxiliary power source device 32 includes a relay 51 , a charge circuit 52 , a discharge circuit 53 , and a capacitor 54 that serves as an auxiliary power source.
  • the relay 51 is disposed between the positive terminal of the main power source 31 and the charge circuit 52 .
  • a point of connection between the relay 51 and the charge circuit 52 is denoted by P 1 .
  • the charge circuit 52 is a circuit configured to charge the capacitor 54 .
  • the charge circuit 52 includes a pair of switching elements 52 A and 52 B connected in series with each other, and a voltage boosting coil 52 C connected between a point of connection P 2 between the switching elements 52 A and 52 B and the point of connection P 1 .
  • the switching elements 52 A and 52 B are n-channel Metal-Oxide Semiconductor Field-Effect Transistors (MOSFETs).
  • the source of the upper switching element 52 A is connected to the drain of the lower switching element 52 B.
  • the source of the lower switching element 52 B is grounded.
  • the drain of the upper switching element 52 A is connected to the positive terminal of the capacitor 54 .
  • a point of connection between the upper switching element 52 A and the positive terminal of the capacitor 54 is denoted by P 3 .
  • the point of connection P 1 is connected to the negative terminal of the capacitor 54 .
  • a point of connection between the point of connection P 1 and the negative terminal of the capacitor 54 is denoted by P 4 .
  • the discharge circuit 53 is connected between the point of connection P 3 and the point of connection P 4 .
  • the discharge circuit 53 is composed of a pair of switching elements 53 A and 53 B connected in series with each other.
  • the switching elements 53 A and 53 B are n-channel MOSFETs.
  • the source of the upper switching element 53 A is connected to the drain of the lower switching element 53 B.
  • the drain of the upper switching element 53 A is connected to the point of connection P 3 .
  • the source of the lower switching element 53 B is connected to the point of connection P 4 .
  • a point of connection P 5 between the pair of switching elements 53 A and 53 B is connected to the motor drive circuit 42 and the power source IC 43 in the EPS ECU 12 .
  • a terminal voltage (battery voltage Vb) of the main power source 31 is detected by a first voltage sensor 61 .
  • a terminal voltage (capacitor voltage Vc) of the capacitor 54 is detected by a second voltage sensor 62 .
  • a voltage (output voltage Vd) supplied from the power source device 30 (discharge circuit 53 ) to the EPS ECU 12 is detected by a third voltage sensor 63 .
  • An output current (battery current ib) from the main power source 31 is detected by a first current sensor 64 .
  • a current (output current id from the power source device 30 ) that flows from the power source device 30 (discharge circuit 53 ) to the EPS ECU 12 is detected by a second current sensor 65 .
  • the second current sensor 65 detects the direction and the magnitude of the current.
  • the direction of the current which is directed from the discharge circuit 53 toward the EPS ECU 12 is determined as positive, and the direction of the current which is directed from the EPS ECU 12 toward the discharge circuit 53 is determined as negative.
  • the detection values from the voltage sensors 61 to 63 and the detection values from the current sensors 64 and 65 are input to the power source control ECU 33 .
  • An ignition state detection signal (not illustrated) that indicates the state of an ignition key is input to the power source control ECU 33 .
  • the power source control ECU 33 controls on and off the relay 51 on the basis of the ignition state detection signal.
  • an ignition state detection signal that indicates that the ignition key has been turned on (hereinafter referred to as an “ignition on state signal”) is input to the power source control ECU 33 .
  • the power source control ECU 33 turns on the relay 51 when the ignition on state signal is input.
  • an ignition state detection signal that indicates that the ignition key has been turned off (hereinafter referred to as an “ignition off state signal”) is input to the power source control ECU 33 .
  • the power source control ECU 33 turns off the relay 51 when the ignition off state signal is input.
  • the power source control ECU 33 controls on and off the four switching elements 52 A, 52 B, 53 A, and 53 B in the auxiliary power source device 32 on the basis of the detection values from the voltage sensors 61 to 63 , the current sensors 64 and 65 , and so forth.
  • the power source control ECU 33 controls the four switching elements 52 A, 52 B, 53 A, and 53 B on the basis of power consumption PS by the motor drive circuit 42 .
  • the power consumption PS is calculated by computing the product of the output voltage Vd which is detected by the third voltage sensor 63 and the output current id which is detected by the second current sensor 65 , for example.
  • the power consumption PS is an example of the “value that matches power consumption by the drive circuit”.
  • the power source control ECU 33 turns off the upper switching element 53 A in the discharge circuit 53 , and turns on the lower switching element 53 B, for example. Consequently, power is supplied to the motor drive circuit 42 by only the main power source 31 .
  • a power supply mode (power supply state) in which power is supplied to the EPS ECU 12 by only the main power source 31 in this way is occasionally referred to as a “normal output voltage mode (normal output voltage state)”.
  • the power source control ECU 33 alternately turns on the pair of switching elements 52 A and 52 B in the charge circuit 52 as necessary. Consequently, the output voltage (battery voltage) at the point of connection P 1 is raised and applied to the capacitor 54 . Consequently, the capacitor 54 is charged.
  • the power source control ECU 33 When the absolute value
  • a power supply mode (power supply state) in which power is supplied to the EPS ECU 12 utilizing both the main power source 31 and the capacitor 54 in this way is occasionally referred to as a “high-output voltage mode (high-output voltage state)”.
  • the power source control ECU 33 limits power to be supplied to the EPS ECU 12 when the operation state of the electric motor 18 is brought into a regeneration state when the power supply mode is the high-output voltage mode.
  • FIG. 3 is a flowchart illustrating operation of the power source control ECU 33 .
  • the power source control ECU 33 acquires the battery voltage Vb, the capacitor voltage Vc, the output voltage Vd, and the output current id (step S 3 ).
  • the battery voltage Vb is detected by the first voltage sensor 61 .
  • the capacitor voltage Vc is detected by the second voltage sensor 62 .
  • the output voltage Vd is detected by the third voltage sensor 63 .
  • the output current id is detected by the second current sensor 65 .
  • step S 5 the power source control ECU 33 computes the power consumption PS by multiplying the output voltage Vd and the output current id which are acquired in step S 3 . Then, the power source control ECU 33 determines whether or not the absolute value
  • of the power consumption PS is not equal to or more than the output voltage switching threshold KE (step S 6 : NO), the power source control ECU 33 turns off the upper switching element 53 A in the discharge circuit 53 , turns on the lower switching element 53 B, and resets the mode flag F (F 0) (step S 7 ). Consequently, discharge of the capacitor 54 is stopped in the case where such discharge is executed. Consequently, in addition, the power supply mode is brought into the normal output voltage mode.
  • the power source control ECU 33 determines whether or not the capacitor voltage Vc is less than a predetermined charge determination threshold A (A>0) (step S 8 ). This determination is made in order to prevent the capacitor 54 from being overcharged.
  • the charge determination threshold A is set to a value that is equal to or slightly smaller than the upper limit voltage of the capacitor.
  • the power source control ECU 33 turns off both the two switching elements 52 A and 52 B in the charge circuit 52 (step S 9 ). Then, the power source control ECU 33 determines whether or not an ignition off state signal is input (step S 13 ). If an ignition off state signal is not input (step S 13 : NO), the power source control ECU 33 returns to step S 3 .
  • step S 8 the power source control ECU 33 starts a charge process for the capacitor 54 (step S 10 ). Specifically, the power source control ECU 33 alternately turns on the pair of switching elements 52 A and 52 B in the charge circuit 52 . Consequently, the capacitor 54 is charged. In the case where a charge process has already been started when a transition is made from step S 8 to step S 10 , the power source control ECU 33 continuously performs the charge process.
  • step S 13 the power source control ECU 33 transitions to step S 13 , and determines whether or not an ignition off state signal is input. If an ignition off state signal is not input (step S 13 : NO), the power source control ECU 33 returns to step S 3 . In the case where it is determined in step S 6 that the absolute value
  • step S 13 the power source control ECU 33 transitions to step S 13 , and determines whether or not an ignition off state signal is input. If an ignition off state signal is not input (step S 13 : NO), the power source control ECU 33 returns to step S 3 .
  • step S 4 the power source control ECU 33 transitions to step S 14 .
  • Vd, Vb, and Vc are the output voltage, the battery voltage, and the capacitor voltage, respectively, which are acquired in step S 3 .
  • the power source control ECU 33 determines whether or not the operation state of the electric motor 18 is the regeneration state (step S 15 ). Specifically, the power source control ECU 33 determines whether or not the sign of the output current id which is acquired in step S 3 is negative and the counter-electromotive voltage Vg which is computed in step S 14 is more than a predetermined threshold B (B>0). In the case where such conditions are met, the power source control ECU 33 determines that the operation state of the electric motor 18 is the regeneration state. In the case where such conditions are not met, the power source control ECU 33 determines that the operation state of the electric motor 18 is a power-running state.
  • step S 15 the power source control ECU 33 transitions to step S 5 .
  • the processes in and after step S 5 discussed earlier are executed.
  • step S 13 the power source control ECU 33 transitions to step S 13 , and determines whether or not an ignition off state signal is input. If an ignition off state signal is not input (step S 13 : NO), the power source control ECU 33 returns to step S 3 . In the case where it is determined in step S 13 that an ignition off state signal is input (step S 13 : YES), the power source control ECU 33 turns off the relay 51 (step S 17 ). Then, the power source control ECU 33 ends the current processing.
  • the power supply mode is switched to the normal output voltage mode when the operation state of the electric motor 18 is brought into the regeneration state in the case where the power supply mode is the high-output voltage mode (see steps S 15 and S 16 ). Consequently, the output voltage from the power source device 30 can be prevented from becoming excessive when the operation state of the electric motor 18 is brought into the regeneration state, and thus occurrence of a failure in the EPS ECU 12 can be suppressed.
  • the power source control ECU 33 when the power supply mode is the high-output voltage mode, the power source control ECU 33 turns on the upper switching element 53 A in the discharge circuit 53 , and turns off the lower switching element 53 B.
  • the power source control ECU 33 may alternately turn on the pair of switching elements 53 A and 53 B in the discharge circuit 53 through pulse width modulation (PWM) control based on the power consumption PS by the motor drive circuit 42 .
  • PWM pulse width modulation
  • the ratio of an on period of the switching element 53 A in the PWM cycle is defined as a duty ratio D 1 [%].
  • the ratio of an on period of the switching element 53 B in the PWM cycle is defined as a duty ratio D 2 [%].
  • D 1 the ratio of an on period of the switching element 53 A in the PWM cycle
  • D 2 (100 ⁇ D 1 ). It should be noted, however, that a dead time is set between the on period of the switching element 53 A and the on period of the switching element 53 B. As D 1 becomes higher, the output voltage from the power source device 30 becomes higher.
  • the power source control ECU 33 computes the duty ratio D 1 in accordance with a deviation
  • a first limit value L 1 which is a normal limit value is used as the limit value L during normal times
  • a second limit value L 2 for overvoltage prevention is used as the limit value L when the electric motor 18 is brought into the regeneration state in the case where the power supply mode is the high-output voltage mode.
  • the first limit value L 1 is set to 100 which is the maximum value of the duty ratio D 1 .
  • a method of computing the second limit value L 2 will be discussed later.
  • FIGS. 4A and 4B are flowcharts illustrating the power source control ECU 33 according to the modification.
  • the power source control ECU 33 acquires the battery voltage Vb, the capacitor voltage Vc, the output voltage Vd, and the output current id (step S 23 ).
  • the battery voltage Vb is detected by the first voltage sensor 61 .
  • the capacitor voltage Vc is detected by the second voltage sensor 62 .
  • the output voltage Vd is detected by the third voltage sensor 63 .
  • the output current id is detected by the second current sensor 65 .
  • step S 25 the power source control ECU 33 sets the limit value L for the duty ratio D 1 for the switching element 53 A during the high-output voltage mode to the first limit value L 1 which is a normal limit value. Then, the power source control ECU 33 transitions to step S 29 .
  • step S 24 the power source control ECU 33 transitions to step S 26 .
  • Vd, Vb, and Vc are the output voltage, the battery voltage, and the capacitor voltage, respectively, which are acquired in step S 23 .
  • D 1 is the duty ratio which is currently set for the switching element 53 A.
  • the power source control ECU 33 determines whether or not the operation state of the electric motor 18 is the regeneration state (step S 27 ). Specifically, the power source control ECU 33 determines whether or not the sign of the output current id which is acquired in step S 23 is negative and the counter-electromotive voltage Vg which is computed in step S 26 is more than a predetermined threshold B (B>0). In the case where such conditions are met, the power source control ECU 33 determines that the operation state of the electric motor 18 is the regeneration state. In the case where such conditions are not met, the power source control ECU 33 determines that the operation state of the electric motor 18 is a power-running state.
  • step S 27 the power source control ECU 33 transitions to step S 25 .
  • the limit value L of the duty ratio D 1 is set to the first limit value L 1 .
  • step S 27 the power source control ECU 33 computes the second limit value L 2 , and sets the second limit value L 2 as the limit value L of the duty ratio D 1 (step S 28 ).
  • a method of computing the second limit value L 2 will be described.
  • a voltage at which the output voltage from the power source device 30 (discharge circuit 53 ) becomes an overvoltage in the case where a counter-electromotive force is generated is defined as Vth, it is necessary to limit the output voltage from the power source device 30 to Vth or less.
  • the second limit value L 2 for the duty ratio D 1 should meet the following formula (3): Vb +( Vc ⁇ L 2/100)+ Vg ⁇ Vth (3)
  • the second limit value L 2 is indicated by the following formula (4): L 2 ⁇ ( Vth ⁇ Vb ⁇ Vg )/ Vc ⁇ 100 (4)
  • step S 29 the power source control ECU 33 computes the power consumption PS by multiplying the output voltage Vd and the output current id which are acquired in step S 23 . Then, the power source control ECU 33 determines whether or not the absolute value
  • step S 30 NO
  • the power source control ECU 33 determines whether or not the operation state of the electric motor 18 is the regeneration state (step S 32 ).
  • the determination method is the same as that in step S 27 discussed earlier.
  • the power source control ECU 33 determines whether or not the capacitor voltage Vc is less than a predetermined charge determination threshold A (A>0) (step S 33 ). This determination is made in order to prevent the capacitor 54 from being overcharged.
  • the charge determination threshold A is set to a value that is equal to or slightly smaller than the upper limit voltage of the capacitor.
  • step S 32 In the case where it is determined in step S 32 that the operation state of the electric motor 18 is the regeneration state (step S 32 : YES), or in the case where it is determined in step S 33 that the capacitor voltage Vc is not less than the charge determination threshold A (step S 33 : NO), the power source control ECU 33 transitions to step S 34 .
  • step S 34 the power source control ECU 33 turns off both the two switching elements 52 A and 52 B in the charge circuit 52 . Then, the power source control ECU 33 determines whether or not an ignition off state signal is input (step S 42 ). If an ignition off state signal is not input (step S 42 : NO), the power source control ECU 33 returns to step S 23 .
  • step S 33 In the case where it is determined in step S 33 that the capacitor voltage Vc is less than the charge determination threshold A (step S 33 : YES), the power source control ECU 33 starts a charge process for the capacitor 54 (step S 35 ). Specifically, the power source control ECU 33 alternately turns on the pair of switching elements 52 A and 52 B in the charge circuit 52 . Consequently, the capacitor 54 is charged. In the case where a charge process has already been started when a transition is made from step S 33 to step S 35 , the power source control ECU 33 continuously performs the charge process.
  • step S 42 the power source control ECU 33 transitions to step S 42 , and determines whether or not an ignition off state signal is input. If an ignition off state signal is not input (step S 42 : NO), the power source control ECU 33 returns to step S 23 .
  • step S 37 the power source control ECU 33 turns off both the two switching elements 52 A and 52 B in the charge circuit 52 (step S 37 ). Consequently, the charge process is stopped in the case where the charge process is being executed.
  • the power source control ECU 33 computes the duty ratio D 1 for the switching element 53 A on the basis of the deviation
  • the limit value L is the second limit value L 2 , which is computed in step S 28 , in the case where it is determined that the power supply mode is the high-output voltage mode and the operation state is the regeneration state, and the first limit value, which is set in step S 25 , otherwise.
  • step S 39 If the computed duty ratio D 1 is equal to or less than the limit value L (step S 39 : YES), the power source control ECU 33 directly transitions to step S 41 .
  • step S 41 PWM control is performed on the switching elements 53 A and 53 B on the basis of the duty ratio D 1 . Consequently, the power supply mode is brought into the high-output voltage mode. Then, the power source control ECU 33 transitions to step S 42 .
  • step S 39 the power source control ECU 33 sets the limit value L to the final duty ratio D 1 for the switching element 53 A (step S 40 ), and thereafter transitions to step S 41 . Consequently, the duty ratio D 1 for the switching element 53 A is limited to the limit value L or less although the power supply mode is the high-output voltage mode.
  • the limit value L is set to the second limit value L 2 , and thus the output voltage for the power source device 30 can be prevented from becoming an overvoltage in the regeneration state.
  • step S 42 the power source control ECU 33 determines whether or not an ignition off state signal is input. If an ignition off state signal is not input (step S 42 : NO), the power source control ECU 33 returns to step S 23 . In the case where it is determined in step S 42 that an ignition off state signal is input (step S 42 : YES), the power source control ECU 33 turns off the relay 51 (step S 43 ). Then, the power source control ECU 33 ends the current processing.
  • the duty ratio D 1 for the switching element 53 A is limited to the second limit value L 2 (see steps S 28 and S 40 ) when the operation state of the electric motor 18 is brought into the regeneration state in the case where the power supply mode is the high-output voltage mode. Consequently, the output voltage from the power source device 30 can be prevented from becoming excessive when the operation state of the electric motor 18 is brought into the regeneration state, and thus occurrence of a failure in the EPS ECU 12 can be suppressed.
  • the main power source power is calculated by computing the product of the battery current ib which is detected by the first current sensor 64 and the battery voltage Vb which is detected by the first voltage sensor 61 .
  • the main power source power is an example of the “value that matches power consumption by the drive circuit”.
  • the auxiliary power source is constituted from one capacitor.
  • the auxiliary power source may be constituted from a plurality of capacitors.
  • the auxiliary power source may be constituted from one or a plurality of power source elements other than the capacitors. Examples of power source elements other than the capacitors include all-solid-state batteries, lithium-ion batteries, and so forth.
  • the power source system according to the present invention is applied to an electric power steering system.
  • the present invention is also applicable to any device for a vehicle that uses an electric motor other than an electric power steering system.

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  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Transportation (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Theoretical Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Physics & Mathematics (AREA)
  • Steering Control In Accordance With Driving Conditions (AREA)
  • Power Steering Mechanism (AREA)
  • Electric Propulsion And Braking For Vehicles (AREA)
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KR102458757B1 (ko) * 2017-11-29 2022-10-26 현대자동차주식회사 리어 휠 스티어링 제어시스템 및 이를 이용한 제어방법
JP7246209B2 (ja) * 2019-03-04 2023-03-27 株式会社小松製作所 作業車両の制御装置、及び作業車両
CN111224657A (zh) * 2019-12-25 2020-06-02 曙光信息产业(北京)有限公司 一种计算机usb端口的电源切换电路
JP2022160301A (ja) * 2021-04-06 2022-10-19 株式会社デンソー モータ制御装置、及び、それを備えるステアリングシステム
EP4253194A1 (en) * 2022-03-29 2023-10-04 KNORR-BREMSE Systeme für Nutzfahrzeuge GmbH Electric power supply system for a vehicle and method for controlling at least one consumer unit of such electric power supply system

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110098887A1 (en) 2009-01-22 2011-04-28 Toyota Jidosha Kabushiki Kaisha Electric power steering device
EP2727796A2 (en) 2012-10-31 2014-05-07 Jtekt Corporation Electric power steering system
US20140222294A1 (en) * 2013-02-01 2014-08-07 Jtekt Corporation Auxiliary power supply device and electric power steering system including auxiliary power supply device
US20150314754A1 (en) * 2012-12-11 2015-11-05 Denso Corporation Vehicular emergency reporting device
US20170210413A1 (en) * 2016-01-21 2017-07-27 Honda Motor Co., Ltd. Power supply device and electric power steering device including power supply device

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3293435B2 (ja) * 1995-11-20 2002-06-17 セイコーエプソン株式会社 モータ駆動装置
JP3805657B2 (ja) * 2001-09-18 2006-08-02 株式会社ジェイテクト 電動パワーステアリング装置
JP3777403B2 (ja) * 2002-04-24 2006-05-24 株式会社ジェイテクト 電動パワーステアリング装置
JP2005219618A (ja) * 2004-02-05 2005-08-18 Koyo Seiko Co Ltd 電動パワーステアリング装置
JP2006304390A (ja) * 2005-04-15 2006-11-02 Favess Co Ltd ハイブリッド車両用電源装置
JP4333646B2 (ja) * 2005-07-06 2009-09-16 トヨタ自動車株式会社 電動パワーステアリング装置
JP4371100B2 (ja) * 2005-11-09 2009-11-25 トヨタ自動車株式会社 バッテリ状態診断装置
JP4228237B2 (ja) * 2006-06-06 2009-02-25 トヨタ自動車株式会社 電動パワーステアリング装置
JP4984320B2 (ja) * 2007-01-12 2012-07-25 トヨタ自動車株式会社 電源制御装置および電源制御方法
JP2011162113A (ja) * 2010-02-12 2011-08-25 Jtekt Corp 電動パワーステアリング装置
WO2014017199A1 (ja) * 2012-07-27 2014-01-30 日産自動車株式会社 車両の制御装置および車両の制御方法

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20110098887A1 (en) 2009-01-22 2011-04-28 Toyota Jidosha Kabushiki Kaisha Electric power steering device
EP2727796A2 (en) 2012-10-31 2014-05-07 Jtekt Corporation Electric power steering system
US20150314754A1 (en) * 2012-12-11 2015-11-05 Denso Corporation Vehicular emergency reporting device
US20140222294A1 (en) * 2013-02-01 2014-08-07 Jtekt Corporation Auxiliary power supply device and electric power steering system including auxiliary power supply device
JP2014150672A (ja) 2013-02-01 2014-08-21 Jtekt Corp 補助電源装置およびこの装置を備える電動パワーステアリング装置
US20170210413A1 (en) * 2016-01-21 2017-07-27 Honda Motor Co., Ltd. Power supply device and electric power steering device including power supply device

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Jan. 7, 2019 Extended Search Report issued in European Patent Application No. 18188216.8.

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